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ericrost Group Title

For Problem Lec.5.3.3: Functions on Lists Part 2 question 12, I don't understand why (length (cons y y)) is 4. For reference y => (1 2 3)

  • one year ago
  • one year ago

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  1. teal Group Title
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    The list is ((1 2 3) 1 2 3), which is 4 items. The first list is only a single item, because it's in car.

    • one year ago
  2. dbastos Group Title
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    Like our friend above says, the first element is a single item. In Lisp, lists can contain any kind of elements. (Even other lists.) In that list of yours, the first element is a list (with 3 elements), but that list with 3 elements is /the first/ element of the list (cons y y). Does that clarify?

    • 5 months ago
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spraguer (Moderator)
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is replying to Can someone tell me what button the professor is hitting...


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